The present invention relates to data processing systems and in particular to a tool for creating a graphical design or graphical user interface.
A designer may use a data processing system to create a graphical design comprising a plurality of graphic objects. The user is provided with a display and a user input to allow manipulation and creation of graphic objects on the display. Typically, a user is provided with a cursor control device, such as a mouse, enabling the user to control one or more cursors on the display. To manipulate the design, the user may select an operation such as a manipulation tool, and then select an object to be the target object to which the manipulation tool is to be applied, typically this is done by loading the cursor with the manipulation tool, usually by clicking on an icon representing the tool, and then applying the tool to the target object.
Often multiple graphic objects may be arranged and simultaneously displayed such that portions of some of the graphic objects overlap and obscure portions of other graphic objects. Sometimes a user will wish to drop a tool onto an object which is wholly obscured by other layers. In this case the user must generally rearrange the order in which the objects are displayed so that at least a portion of the desired graphic object appears before the manipulation can be made.
Typically, this is done by the user selecting a tool for sending successive layers of objects to the back of the arrangement or bringing successive layers to the front, thereby scrolling through the different layers one by one until the desired target object is on top. The user can then select and drop the source object onto the target object as described above. The user must then rearrange the objects to return them to their original order.
In another method of rearranging the layers, the user is presented with a tree showing the containment hierarchy of the objects which allows the user to select the object of interest, which will then appear on the display. However, the selected object is often drawn at a default size and location and must then be resized and relocated by the user, which is not convenient.
Another method is described in IBM's U.S. Pat. No. 5,377,314. In this method a user selects a particular area of the screen, and is then able to scroll through only those graphic objects which are at least partially displayed within the selected area of the screen. This reduces the number of objects which are scrolled through and speeds up the selection of the desired target object. When an object is selected it becomes the outermost layer. The user can later request that the objects be returned to their original layer order.
There is still a need however for an improved method of manipulating objects that may be obscured by overlying layers.